1. Field of the Invention
This invention relates to a method for the delivery of substantially identical dosages of medicament at substantially identical rates to each of a plurality of domestic animal drinking stations, wherein the inventive method has the attendant advantages of increased sterility and increased protection from adverse environmental conditions in the delivery of medicaments.
This invention further relates to an apparatus for accomplishing this method, which apparatus includes a common source medicament reservoir connected to a plurality of animal drinking stations in such a manner that the above-described conditions relating to dosage, dosage rate, sterility and environmental shielding are implemented.
2. Description of Related Art
Domestically raised poultry are subject to a variety of infectious diseases, many of which are controlled through vaccination using modified live or killed vaccines. It has been discovered that oral vaccination through the water supply provides a simple and inexpensive method to immunize poultry against infectious agents. For instance, it has been found that the oral administration of a modified live Newcastle Disease Virus (NDV) vaccine administered in drinking water protects poultry against experimental challenge with virulent NDV isolates, as well as against natural exposure with this virus.
Vaccines for oral immunization are often administered in poultry houses by adding the vaccine to a common outlet such as a drinking water reservoir using "proportioner" apparatus. Proportioner apparatus are described in U.S. Pat. No. 3,937,241 to Cloup and U.S. Pat. No. 4,060,351 to Cloup, both of which are hereby incorporated by reference in this application. This type of field vaccination practice does not optimize vaccine delivery conditions with respect to vaccine titer or sterility and thus may result in poorly vaccinated or unvaccinated flocks.
Medicaments may also be administered non-orally by a variety of methods and with a variety of apparatus. One such apparatus is described in U.S. Pat. No. 5,468,227 to Haskell, which describes a solenoid driven hypodermic needle which pierces the wing of a bird. A positive displacement pump delivers medicament to the needle for administration. The Haskell apparatus has the obvious disadvantage of requiring that each bird to be treated must be captured and handled prior to administration. Thus, Haskell discloses a relatively inefficient method of medicament administration. Moreover, due to its construction, the Haskell apparatus may be inoperative with respect to animals other than birds which may not possess anatomical features, such as a bird's wing, which are easily or effectively pierced.
Stowe, in U.S. Pat. No. 4,643,354, describes an apparatus for high volume vaccination in which a vaccine is atomized in close proximity to poultry cages. Vaccine is then ingested by the treated birds via inhalation. Although this apparatus accomplishes high volume vaccination, it too has several disadvantages. First, atomized vaccine may not be easily administered due to air currents, wind and the like. Further, atomized vaccine has only a limited effective airborne time, and vaccination would necessarily have to result shortly after atomization. When applied to medicaments such as antibiotics for which sustained dosing is preferred, the atomization apparatus would be either ineffective or would cause logistical problems due to its being cumbersome. Moreover, the Stowe apparatus employs a "shotgun" approach to medicament administration, where a large amount of medicament is atomized to insure that a small amount of medicament actually is ingested. As the majority of atomized vaccine will not be ingested, Stowe is wasteful of expensive medicaments.
It has therefore been found desirable to provide a system which would deliver vaccine at a specified flow rate and provide for a more sterile reservoir environment which would lead to better vaccination rates and more effective control of infectious diseases. Such a system would also be useful for oral administration of medicaments to any other type of domesticated animals.